I believe Mamdani’s plan, which at this point is only a proposal, or, as you say, a politician’s dream sheet to appease voters, applies only to condos, co-ops, and 1- to 3-family homes, not the part time dweller’s apartment he uses while working in NYC.There are two people in my building that live bi-coastal (SF/NYC) and own residences in both. These guys run tech firms so they hire a number of people in each city as well as contribute a fair amount to the tax coffers. That they aren't in each City 365 days a year doesn't change that.
The idea that they are viewed negatively for doing so says more about us than them.
To use the “invisible hand”model, if the business is there, which it must be for one to travel back and forth, one part time dweller who employs others will be replaced by another willing to pay the new tax
And why would anyone give up NYC to reside in San Francisco?